Hendra Virus causes a rare but often fatal disease in horses and humans, only recognised since 1994 when a number of horses and their trainer died from the disease. It seems clear that the virus has been infecting horses for some time but remain undiagnosed until a horse infected a human.

It is not to be confused with Australian Bat Lyssavirus.

 

All 4 species of Australian flying foxes are a reservoir for Hendra, though they show no clinical signs of being unwell when infected. All the evidence suggests that Hendra virus has co-existed with flying foxes for a very long time. It is still unknown how horses come into contact with the virus, but research is being directed mainly at flying fox excretions such as urine.

From 1994 until 2011 the 14 recorded outbreaks were dispersed and intermittent with a maximum of two outbreaks per year seen. In 2011 there was a significant increase in the number of outbreaks,13 horses dead at 10 locations in QLD and 10 horses dead at 8 locations in NSW. This led to substantial funding for research into the virus from the State and Federal governments. CSIRO very quickly developed a protective vaccine for horses, Equivac HeV, which was released in November 2012. Horses are vaccinated with two doses given three to six weeks apart. Immunity occurs 21 days after the second dose. Six monthly  boosters are recommended.

Unfortunately there has been very little uptake of the vaccine by horse owners in the first year of the it's availablity..

Prevention is aided by limiting exposure of horses and their feed to fruit bat excretions and by the use of proper personal protective equipment particularly when dealing with sick horses. Some risk exists prior to the onset of clinical signs in horses, so prevention is all about good hygiene practcies around horses all the time.

Blood taken in the 1990s from those in close contact with flying foxes and their excretions, namely flying fox carers, showed no signs of their coming into contact with the disease ie no antibodies. There is no evidence that humans can contract Hendra Virus from flying foxes, only from horses.

For further information, search 'Hendra Virus'on these websites:

Biosecurity Queensland

fQueensland Health

CSIRO

Queensland Horse Council

Australian Wildlife Health Network

Federal Department of Agriculture, Fisheries and Forestry